Managing the risk of non-indigenous marine species transfer in Singapore using a study of vessel movement

Findings from vessel movement information in a major port terminal in Singapore showed that vessel residence time is short, with > 92% of vessels spending seven days or less. There was little variation in vessel residence time to vessel arrival numbers, while the top three last ports of call were found to be from regional ports. Using two key features obtained from vessel movement records, 1) vessel residence time and 2) biogeographic origin of the vessels' last port of call, a simple risk assessment matrix was constructed and applied to assess the level of risk of NIMS transfer by transiting vessels.